Turning a laptop screen into an external monitor.

So my old Dell L502x died. However most of the components were fine, it's just the motherboard that seemed to be down with a case of water damage. So along with turning the chassis of the laptop into a dock/stand for my new laptop I wanted to turn the laptop's screen into an external monitor.

So the first thing I did was extract the panel from the housing to take a look at the model number and the interface. If you're looking to do this yourself just look up the documentation for your laptop or go to ifixit.com and look it up. Fortunately Dell has excellent documentation and a pretty straightforward teardown process.

Sweet. Panel extracted. Next step was to look up on the internet for a suitable controller board for the panel. Simple case of Googling "B156HW01 V.7 HDMI controller board". VGA ones are a lot more common, but I'd rather have a digital input for ubiquity. This search didn't really yield much of what I wanted though. Mostly just combined solutions that came with a panel like this one. However a little deeper searching found me this one. While it wasn't specific to my model number, it was indeed compatible.

The folks over at njytouch are pretty excellent, so if you're in doubt just message them your panel manufacturer and model number and they'll let you know which controller board is suitable.

Mine took a week or so to arrive, so in the meantime I built myself a stand out of Meccano and an old speaker mount:

When your board actually arrives it should consist of the main controller board, a button board and cables to connect everything up. It will look something like this:

Sweet, let's disconnect the panel's original cable and connect it all up.

Woop. New one fits perfectly. Next step is to plug everything else in and make sure it all works alright.

Bonus picture re-assembled with the Meccano stand:

Well that sure functions well enough! Lets be honest though, that doesn't really look amazing. Wires and boards hanging out everywhere, not really the cleanest. I kinda wanna mount all this tech to the monitor itself. Fortunately the controller board has mounting holes.

Time to place everything on the panel to map out how we want to mount it. Using a permanent marker mark out the holes for drilling the mount holes. Bonus: mark out some slots so we can route the wires in the screen's housing opposed to having them dangling everywhere.

Using my trusty dremel I drilled and dremeled out the holes and slots we just marked. It might sound obvious, but make sure you remove the actual LCD panel before you attempt to do this.

And here's what the underside of the rear-housing look like with all the holes and slots cut out:

Next step is to route the wires and affix the board into place.

Next I took some screws, spacers (also Meccano), washers and nuts to fix the board to the panel's housing.

Next I plugged in all the cables to the board.

The button board didn't have any mounting holes so I just velcro'd it to the housing.

Next thing to do was to plug the panel in again and re-assemble everything.

Not bad, but I feel it's missing something... The controller board just looks so fragile and bare just mounted there with no protection. I guess the only thing to do is make something to cover it. I considered getting something 3D printed to make it look nice, but that would be way too sensible. Instead I used one of those old Helix Oxford pencil cases. I drilled out holes to match the ones on the controller board and acquires some spacers. As such:

Then It was just a case of putting the spacers on top of the screws already on the controller board, putting the pencilcase on top of that, and finally tightening the nuts on top of both of those.

Not too shabby if I say so myself. Here's the final result, also an interesting bit of backlight bleeding through the dremel slots.

Thanks for posting! I'm doing the same with an old HP laptop monitor. I purchased the controller board and power adapter, and the display is VERY dim (almost not visible). Is there something silly I'm doing wrong, or is perhaps the monitor donezo?

It will work, but the CFL will likely need an inverter board. If you search for your model in eBay or something, I'm sure you'll come across a kit that has both the controller and inverter boards. If nothing else, always good to ask a seller. Good luck!

It will work, but the CFL will likely need an inverter board. If you search for your model in eBay or something, I'm sure you'll come across a kit that has both the controller and inverter boards. If nothing else, always good to ask a seller. Good luck!

Awesome build, but with the casing of the controller board, (I'm about an intermediate in electronics) have the power to hold static charge? if the casing is metal, would it occasionally static zap the board? or am I just being a dork? Nice build tho

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